Telephone system



` Aug. 22, 1933.

A. wlEssNER 1,923,352 TELEPHONE SYSTEM Filed Feb. 19, 1932 2 Sheets-Sheet 2 Patented Aug. 22, 1933 TELEPHONE SYSTEM Alfred Wiessner, Berlin-Charlottenburg, Germany,assignor to Siemens & Halske Aktiengesellschaft of Wernerwerk, of Siemensstadt near Berlin, Germany Application February 19, 1932, Serial No. 594,065, and in Germany March 12, 1931 9 Claims. (Cl. 179-46) This invention relates to a circuit arrangement for initiating switching operations over inductively connected lines in telephone systems.

It solves the problem of causing various switching operations to be performed at the incoming end of a line in consequence of the various manners in which switching means at the outgoing end of said line have been actuated.

' This is achieved by switching vmeans for transl mitting induced impulses being arranged at the outgoing end of the line, said switching means causing an impulse receiving relay at the incoming end' of the line to be momentarily energized 4 when a switch is thrown over and permanently energized upon said switch being restored to its original position.

An embodiment of the invention is shown in the drawings, said embodiment illustrating the use of the inventionin automatic telephone sys- '270i tems and showing the simple manner in which the device according to the invention seizes and releases various connecting devices. The reference letters TSt in Fig. l represent a subscribers station inductively connected to the one end of the subscribers line TL, and Ue a repeater connected in the same way to the other end of the line TL. Fig. 2 shows the succeeding preselector VW and group selector GW. j

The varrangement operates in the following manner:

When the subscriber at the station TSt lifts his receiver, the switch hook Hs is closed and a circuit for relay S is set up over said switch hook. Relay S is energized and closes contact 1s which results` d' in a circuit being closed over: earth, battery,

contacts 3121, 1s, winding I of the transformer T1',-

earth. Contact 2s also :is closed and consequently relay V1 is connected up upon the energization .of

relay S. Relay V1, when energized, throws contact 3111 over into positionflvl Vwith the result that the circuit set vup by the closing of contact 1s is again cut oi. Contact 53 being opened no cur'- rent is able to flow over contact 2in1.

The closing of the switch hook Hs therefore sets up the circuit whicliextends over winding I of the transformer Tr momentarily only. An impulse therefore, is induced in Winding III of the transformer at the closing of this circuit as well as at the opening of said circuit. These two induced impulses reach the speaking current repeater S10 I and thence over the line TL the repeater SP2 from which they are repeated to the impulse receiving relay P1 overrcontacts 6h and 7h. The' last mentioned relay is constructed as a polarized relay having a neutral normal position and is actuated by the received impulses in such a manner that its armature is Vthrown over in a position corresponding to the direction of theimpulses. 4

The first impulse, that is tosay, the impulse produced on the closing of contact 1s influences A relay P1 in such a manner that it throws over its armature, thus'closing contact SpL-whereas the second impulse, that is to say, the impulse produced by the opening of contact 3111 influences relay P in the opposite direction causing it to restore its armature to normal, Relay J is energized over 5' contact 8 p1 and closes contact9i and also connects up relay 'Dover earth,` contact 91', relay D, resistance W l, battery, earth. Relay D closes its contacts 10d, 11d, 12d, 13d and llldand opens contact 15d. Contact 14d sets up a locking circuit 7o for said relay, and the succeeding preselector VW is seized over contact 10d, a circuit Vfor relay R2 being'closed over: earth, battery, resistance W2, contacts 10d, 26e, blead, relay R2, earth. Relay R2 in the preselector VW in Fig. 2, therefore, is energized and closes contacts 1672 and 1'712. This sets up a'circuit for the rotary f magnet over: earth, battery, contacts 1612, 181?, rotary magnet D, interrupter U, and causes the circuit of the magnetv D to be intermittently closed and opened ywith the result that the switch wipers yof the preselector are advanced until an idle succeeding group selector has been reached. e

' When this occurs relays T andC are ener- 85 gized over: earth, battery, contacts 1'7r2, relayA T, c-wiper of the preselector, c-lead, off-normal contact 22k, winding I of 'relay C, earth. Relay T :puts its contact 18t into position 19t and thus disconnects the rotary magnet D which inturn brings `the preselector to rest.V In addition, Ait closes its contacts 291i and Zit, thus switching through the speaking leads to the group selector.` Contacts 23e and 27e are closed when relay C is energized. Due to the switching through oi Vthe speaking leads, relay R1` in the repeater Ue is energized in series with relays A and B in the group selector GW. Relay R1 closes its contacts 32H and consequently causes Arelay E to be energized. This relay closes its contacts 33e 100 and 34e and opens contact 26e. In addition, contact 43M is openedby relay R1. Relay A places its contact 24a in the position 25a with the result that relay V1 is energized over: earth, battery, contact 23e, winding II of relay C, contact ,105 25a, relay V3, earth. Relay V3 opens contact 28r3 and closes contact 29123. This prepares the seizure of the succeeding but not shown iinal Y selector. y

When, for the purpose of setting the switch,

the time the called subscriber has hung up.

the subscriber operates his dial, contact a in Fig. 1 is intermittently closed which sets up a circuit over: earth, battery, contact 30a, windm ing I of the tranformer Tr, earth. The induced currents generated by the closing of this circuit in winding III of the transformer are transmitted in themaner described above to the impulse receiving relay Pl, which upon receiving these impulses connects up relay J by means of its contact Sp1 and thus causes the-impulses to be transmitted to relay A of the group selector over contact 311'. This relay actuates the not shown vertical magnet of the group selector and causes the switch Wipers of said group selector to be raised to the required level and laterto hunt for an idle nal selector at the end of the impulse series in the usual manner. The further setting up of the connection to the required subscriber takes place in known manner and is not described in detail since this is not necessary for the understanding of the invention. Relay V4 is energized at the commencement of the impulse series for the setting of the iinal` selector due to the closing of contact 24a, remains energized during the complete impulse series and b'ypmeansof contact 53114 applies control potential tothe outgoing b-lead. Relay P2 also is energized and closes its contacts 35p2, 36122 and 3'7p2. f

When, at the end of the conversation, theY called subscriber replaces his receiver, potential will be applied to the b-lead -in the not shown final selector, thuscausing relay Bl to be energized over: earth, relay B1, Contact 27o, winding of the speaking current repeater S123, contacts 38114, 36102, b-wiper ofthe group selector, b-lead,

' battery applied to this lead in the final selector, earth. Relay Bl closes contacts ',39b1, thus releasing relay C dueto its winding I being disconnected by the opening of the voff normal contact 22k at the first vertical step of the switch. Relay C opens contact 23o which causes relay V1 also to be released. This opens contact 29123 so .that relay P2 releases'. Consequently contact 40p2 is closed and sets up a -circuit'for the l release magnet M over: earth,'app1ied to the oil normal contact 41k which is lclosed at the :first vertical step, contacts 401:2, 28113, magnet M, battery, earth; tor to normal in -known manner. in addition, opens its contact 42m the c-lead to the' T to release. Contacts 20t and 2li are consequently opened and contact 18t closed. f It will now be assumed r`thatthe calling vsub- The magnet, which breaks scriber has not yet replaced his receiver. Due

to the opening of contacts 20t and 21t, relay R1 in the repeaterfUe is caused'to release With the result that contact 43r1 is closed and contact 3211 is opened.r Relay H will, therefore, be

,y connected up over: earth, contacts 43r1, 34e, re-

lay H, battery, earth. Relay H closes contact 44h which causes relay D to release. This, in

- turn, opens contact 10d'and cuts olf battery from their-lead. This disconnection takes place before relay E has closed its contact 26e as relay E releaseswith very ingof contact 13d. This prevents thev preselector Vw from operating afresh if the calling subscriber should not have replaced his receiver at is cut 01T by the opening of the switch hook Hs so that contacts 1s and 2s are opened and con- Magnet M restores the group selec- Y preselectorl and causes relay' slow action upon the open'-v k to the impulse produced in Winding III of the transformer on the closing of contact 1s in the manner described above. Therefore, it has no eiect on` relay P1. Only the induced impulse produced on the opening of contact 4111 aiects relay P1 causing said relay to actuate its armature and retain it in its operative position until it is restored to normal in the manner to be more explicitly described below.

Relay P1, thus, has closed Contact Sp1 and thereby connected up relay J. Due to thisoperation contacts'45y', 467' and 477' are'closed. A circuit forrelay V2 is setup over: earth, contacts 12d, 457', relay V2, resistance W3, battery, earth, as contact'12d is closed. `Relay V2.closes contactsy 49122 and 50112. This produces a short circuit for relay D over. contacts 467' and 50v2, which` causesrelay D to release and disconnect battery from the blead to the preselector by means of contact 10d. Contact 15d alsov is closed upon the release of relay D so that relay kHis, connected up over: earth, contacts 477', 15d, relay H, battery, earth. This relay is energized and closes' its contacts'lh,y and 52h, and thus completes a circuit for relay P1 in which the current extends insuch a direction that vthe relay restores its armature to normal and consequentlyreopens contactv Bpl, Contact 487' is closed on the release of relay J, causing relay V2 to release due to the short circuit produced thereby. The contact 11d being opened upon the release of relay D, relay R1 also releases with the resultthat all the switching means associated with the repeater are' restored to normal. j

The succeeding connecting devices are then released in the vmanner, described` above by the called subscriber replacing his receiver.

The invention is ,not limited to the embodiment described. Thev switching means Yfor the nected subscribers line, an impulse receiving de- Vice at the incoming endof said line, a transformer at the `outgoing end lof said line, means responsive tothe removal of the receiver by a calling subscriber for closingr and opening a circuit including the primary winding of said transformer, said device operated responsive to the induced current generated byuthekclosure of said circuit and restored to normal responsivey to the inducedl current generated by the vopening of said circuit, and means responsive when the calling subscriber replaces the receiver for momentarily closing the circuit including the primaryrvvinding and for altering the same so that the device will operate only responsive to the induced current generated by the opening of said circuit.- 2. In a telephone system, an inductively connected subscribers line, `an impulse receiving device at Ithe incoming end of saidv line,-a trans-V former atV the outgoing end of said linepmeans responsive to the removal of the receiver by a calling subscriber for closing and opening a circuit including the primary winding of said transformer, said device operated responsive to the induced current generated by the closure of Vsaid circuit and restored to normal responsive to the induced current generated by the opening of said circuit, means responsive when the calling subscriber replaces the receiver for momentarily closing the circuit including the primary winding and for altering the same so that the device will operate only responsive to the induced current generated by the opening of said circuit, and means controlled by said device for subsequently restoring said device to normal.

3. Inl an automatic telephone system, a subscribers line terminating in a repeater, a transformer at the subscribers end of said line having its secondary Winding bridged across the line conductors, a polarized relay in the repeater, a twosection primary Winding for said transformer, means responsive to the removal of the receiver by a calling subscriber for momentarily completing a circuit including the iirst section of the primary winding to induceV current in the secondary winding, the induced current generated by the closing of the primary circuit being of the direction to operate the polarized relay and the current generated by the opening of the circuit being of the reverse direction to restore the relay to normal, means in said repeater responsive to the momentary operation of said relay for extending said line to an automatic switch, a second circuit including the rst section of the primary winding momentarily completed to transmit induced impulses to operate said relay when the subscriber dials, means controlled by said relay for repeating the impulses to set the automatic switch, means responsive when the calling subscriber hangs up his receiver for momentarily completing a circuit including the second section of the primary winding, the induced current generated by the `closing of this circuit being of the reverse direction required for operating the relay and the induced current generated by the opening of this circuit being in the proper direction for operating the relay, and means responsive when the relay remains in its operated position for releasing the automatic switch and for energizing the relay to restore the same to normal to release the repeater.

4. In an automatic telephone system, a subscribers line terminating in a repeater, a lineswitch individual to said repeater for extending said line to an automatic switch, a transformer at the subscribers end of said line, means responsive to the removal of the receiver by a calling subscriber for momentarily closing a circuitl including the primary Winding of said transformer to transmit induced impulses over said line, a polarized relay in said repeater operated responsive to the induced current generatedby the closing of said circuit and restored to normal responsive to the induced current generated by the opening of said circuit, means responsive to the momentary operation of said relay for operating said lineswitch to extend said line to an automatic switch, means vfor operating said polarized relay to repeat impulses dialled by said subscriber to set the automatic switch, means responsive when the calling subscriber hangs up for momentarily closing the primary circuit and for altering the same so that the polarized relay will not operate responsive to the induced current transmitted when the circuit is closed and will operate when the circuit is opened, and means responsive when saidrelay remains in its operated position for releasing said lineswitch and automatic switch and for energizing said relay to restore it t normal to release the repeater.

5; In an automatic telephone system, a calling subscriber, a switch in an exchange, means at the subscribers station for transmitting impulses, ak

polarized relay in said switch momentarily operated by each of the impulses transmitted to set said switch to establish a connection, means at the subscribers station for transmitting an impulse when the subscriber hangs up, said relay adapted to remain in its operated. positionrresponsive to the impulse transmitted when the subscriber hangs up, and means in said switch operated when said relay remains in its voperated position for releasing said switch and said relay.

6. In an automatic telephone system, means at a subscribers station for making and breaking a circuit including a winding of a transformer to transmit induced impulses, a relay in an autoinduced current generated on the make of the altered circuit and to energize and remain in its energized position responsive to the induced current generated on the break, and means operated when said relay remains in its energized position for releasing said switch. and for completing a circuit for releasing said relay.

7. In combination, a telephone line, a transformer having the secondary winding connectedv to said line, means responsive to the removal of the receiverfor automatically closing and opening a circuit through the primary Winding, thereby inducing twoimpulses in the secondary winding, and means responsive to the replacement of the recevier fory automatically closing and opening a reversed circuit `throughthe .primary winding, thereby inducing two impulses in the secondary winding which are of opposite polarity,

respectively, as regards to said first two induced impulses. i l 8.1n combination, a telephone line, a telephone instrument, means responsive to the removal of the receiver and also to the replacement thereof for automatically transmitting two impulses oi opposite polarity over said line, and means for automatically reversing the order in which thesecond pair of impulses are transmitted. Y

9. A telephone system which includes a telephone instrument and line as set forth in claim 8, which is further characterized by the provision of a polarizedrelay and an automatic switch at the exchange, said relay being responsive to a pair of impulses received in normal order to operate said switch and responsive to a pair of impulses received in reverse order-to release said switch.

ALFRED WIESSNER. 

